In the Russian and world practice while developing guidelines in accordance with the EBM principals an assessment of the certainty in the evidence and strength of recommendations is carried out.
One of the most common system of rating certainty of evidence and strength of recommendations is GRADE developed in 2000 (the Grading of Recommendations Assessment, Development and Evaluation). According to GRADE, while assessing certainty of evidence developers of guidelines define correlation of “benefit and harm” – correlation of likelihood of a beneficial effect and undesirable effects related to medical intervention or other circumstances related to medical care.
The survey was conducted using electronic database Pubmed and EMBASE, apart from that, information from GRADE website as well as websites of a few professional medical associations was analyzed, who confine to GRADE methodology including American College of Physicians (ACP), The Endocrine Society, Kidney Disease: Improving Global Outcomes (KDIGO).
As a result of the analysis of the published literature universal transparent quantitative methods for assessing “benefit-harm” correlation, which can be used for developing Russian guidelines, were not discovered. In most foreign guidelines a group of experts developing guidelines by reaching a consensus defines this correlation:
- In GRADE methodological recommendations 2016 they pay great attention to developing guidelines of the “benefit-harm” correlation, however, unique methodology of their assessment is not mentioned. GRADE Handbook states that authors should use their personal perspective while making a decision on what a significant benefit and harm represent and justify their chose by reviewing various cases.
- The guidelines that were developed using GRADE system often lack information on methods for defining “benefit-harm” correlation (e.g. Clinical Practice Guidelines by the Infectious Diseases Society of America 2018) or it is stated that definition of this correlation is the result of reaching a consensus between experts-developers of guidelines (e.g. American Endocrine Society Clinical Practice Guideline “Congenital Adrenal Hyperplasia Due to Steroid 21-Hydroxylase Deficiency”)
The survey also revealed quantitative methods for assessing “benefit-harm” correlation outside the GRADE system and guidelines developments. For instance, the review carried out in 2010 by the Academic Health Center of the Cincinnati University (Ohio, USA), describes several methods including those where “benefit-harm” correlation is considered to be the number needed to treat (NNT) for having a very satisfactory outcome for one patient corresponding to the number needed to harm (NNH). Such clinical methods are often used to assess clinical efficacy and safety of a particular medicine, however, no examples of applying such methods while developing guidelines have been found.